Collar assembly for securing consumables of an arc welding apparatus

ABSTRACT

An arc welding apparatus includes a conductor tube assembly that has a collar assembly with a collar body that is biased by a spring. A consumable assembly is mechanically secured to the conductor tube and displaces the collar body and the collar body imparts a biasing force against the consumable assembly pretensioning the consumable assembly on the conductor tube assembly.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. provisional application Ser.Nos. 61/903,950 filed on Nov. 13, 2013 and 62/053,784 filed on Sep. 22,2014. The disclosures of the above applications are incorporated hereinby reference in its entirety.

FIELD

The present disclosure relates generally to welding apparatuses, andmore particularly to arc welding apparatuses such as Metal Inert Gas(MIG) or Gas Metal Arc Welding (GMAW) welding guns, includingconsumables for generating a welding arc and diffusing a shield gas.

BACKGROUND

The statements in this section merely provide background informationrelated to the present disclosure and may not constitute prior art.

In an arc welding apparatus, such as Metal Inert Gas (MIG) or Gas MetalArc Welding (GMAW) welding gun, a welding wire is fed through thewelding gun to provide a molten metal pool to join metal workpiecestogether. An inert gas is directed through the front (distal) end of thewelding gun to provide a surrounding layer or blanket of shielding gasto protect the molten metal pool from atmospheric contamination. Theinert gas is typically a combination of various gases such as argon orhelium, among others.

A prior art MIG or GMAW welding gun typically includes a contact tip anda gas diffuser connected to the contact tip. The contact tip has acentral bore to guide the welding wire to the workpieces. The contacttip transfers electrical current to the welding wire. The gas diffuseris typically threaded to the contact tip and defines gas passagewaysthat direct the shielding gas into a blanket of shielding gas around themolten metal pool. The contact tip and gas diffuser are constantlysubjected to high heat and are susceptible to wear due to hightemperature operation.

SUMMARY

The present disclosure generally provides a contact tip/diffuserconfiguration for an arc welding apparatus, such as an MIG or GMAWwelding gun with an increased consumable life. The various forms of thepresent disclosure provide a simplified structure, more uniform heatdistribution and improved cooling to increase consumable life, amongother benefits.

In one form, a collar assembly for use in securing a nozzle assembly toa welding torch is provided. The collar assembly comprises a collar bodydefining an exterior surface and an internal bore, and an internalflange extends radially and inwardly disposed at a distal end portion ofthe collar body. A wave spring is disposed against the internal flangeand a locking ring is disposed against the wave spring.

In another form, a collar assembly for use in securing a nozzle assemblyto a welding torch is provided. The collar assembly comprises a collarbody defining an exterior surface and an internal bore, and an internalflange extends radially and inwardly disposed at a distal end portion ofthe collar body. A wave spring is disposed against the internal flangeand a conductor tube defines an outward protrusion for engaging againstthe wave spring opposite the internal flange.

Further still, an arc welding apparatus comprises a conductor tubehaving a distal portion defining an external surface profile and anoutward protrusion. A collar assembly comprises a collar body thatdefines an exterior surface and an internal bore. The internal borefurther defines a distal portion having a distal diameter and a proximalportion having a proximal diameter. The distal diameter is smaller thanthe proximal diameter. A wave spring is disposed between the body andthe exterior surface of the conductor tube and the wave spring biasesthe collar body between the outward protrusion and the distal portion. Asleeve comprises a body having a proximal end portion and a distal endportion. The body defines an inner and outer surface profiles. The innersurface profile is configured to slidably engage over the externalsurface profile of the conductor tube. The outer surface profilecomprises a threaded portion. The sleeve engages against the collar bodyand secures the collar body on the conductor tube. A consumable assemblyhas an inner body. The inner profile is configured to mechanicallyattach to the threaded portion of the sleeve. The inner body has adistal end has an internal distal flange. A contact tip defines anexternal shoulder configured to abut the internal distal flange forsecuring the contact tip to the conductor tube. The inner body isthreaded onto the thread portion of the sleeve and the inner bodyengages against the collar body displacing the collar body causing thewave spring to exert a biasing force through the collar body against theinner body pretensioning the consumable assembly on the threadedportion.

Further areas of applicability will become apparent from the descriptionprovided herein. It should be understood that the description andspecific examples are intended for purposes of illustration only and arenot intended to limit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustration purposes only and arenot intended to limit the scope of the present disclosure in any way.

FIG. 1 is a perspective view of an arc welding apparatus constructed inaccordance with the teachings of the present disclosure;

FIG. 2 is a cross-sectional view of a consumable assembly and a partialconductor tube and conduit liner constructed in accordance with theteachings of the present disclosure;

FIG. 3 is a cross-sectional view of a consumable assembly and aconductor tube assembly constructed in accordance with the teachings ofthe present disclosure;

FIG. 4A is partial side view of a conductor tube assembly constructed inaccordance with the teachings of the present disclosure;

FIG. 4B is a partial side cross-sectional view of the conductor tubeassembly of FIG. 7A;

FIG. 4C is a partial exploded side cross-sectional view of the conductortube assembly of FIG. 4A;

FIG. 5 is a side view of a sleeve for a conductor tube constructed inaccordance with the teachings of the present disclosure;

FIG. 6A is a partial side cross-sectional view of a conductor tube and acollar assembly constructed in accordance with the teachings of thepresent disclosure;

FIG. 6B is a perspective view of a collar body of the collar assembly ofFIG. 6A;

FIG. 6C is a side view of the collar body of FIG. 6B;

FIG. 6D is an cross-sectional view of the collar assembly of FIG. 6B;

FIG. 7 an enlarged partial side cross-sectional view of the conductortube assembly constructed in accordance with the teachings of thepresent disclosure

FIG. 8 is a cross-sectional view of a consumable assembly and aconductor tube assembly constructed in accordance with the teachings ofthe present disclosure;

FIG. 9 is an exploded perspective view of a conductor tube assembly anda consumable assembly constructed in accordance with the teachings ofthe present disclosure;

FIG. 10 is a top view of one form of a nozzle body, collar assembly andconductor tube assembly in accordance with the teachings of the presentdisclosure;

FIG. 11A is a partial cross-sectional view of the nozzle body of FIG. 10in an initial position;

FIG. 11B is a partial cross-sectional view of the nozzle body of FIG. 10in a first position;

FIG. 11C is a partial cross-sectional view of the nozzle body of FIG. 10in a second position; and

FIG. 11D is a partial cross-sectional view of the nozzle body of FIG. 10in a third position.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is in no wayintended to limit the present disclosure or its application or uses. Itshould be understood that throughout the description and drawings,corresponding reference numerals indicate like or corresponding partsand features. And although the term “MIG” or “GMAW” is used throughoutthe specification, it should be understood that the teachings of thepresent disclosure apply to any type of welding or cutting apparatus.

Referring to FIG. 1, an arc welding apparatus, such as a MIG or GMAWwelding gun, is illustrated and generally indicated by reference numeral10. The MIG welding gun 10 includes a handle 12, a conductor tube 14attached to the handle 12, and a consumable assembly 16 attached to theconductor tube 14. The handle 12 is connected to a welding cable 18 thatcarries welding current, shield gas, and a welding wire (not shown) froma power source (not shown), a gas source (not shown), and a wire feeder(not shown) to the welding gun 10.

The consumable assembly 16 includes a plurality of consumable componentsincluding a nozzle assembly 22 and a contact tip 24 inside the nozzleassembly (contact tip 24 is shown in later FIGS. 2 and 3). The structureand operation of an exemplary arc welding apparatus has been disclosedin U.S. Pat. Nos. 5,491,321 and 5,338,917, which are commonly owned bythe assignee of the present application, and the contents of which areincorporated herein by reference in their entirety.

The consumable assembly 16 is connected to a distal end portion 26 ofthe conductor tube 14. The nozzle assembly 22 is substantiallycylindrical in one form and receives the distal end portion 26 of theconductor tube 14 therein. The contact tip 24 is coaxially disposedinside the nozzle insert 22 and may be secured therein as illustratedand described in copending U.S. application Ser. No. 13/674,829 titled“Hollow Contact Tip-Diffuser for GMAW Manual/Robotic Arc Welding MIGGuns,” which is commonly owned with the present application and herebyincorporated by reference in its entirety. Further construction andoperation of an exemplary arc welding apparatus for which the teachingsof present disclosure may be applied are also described in greaterdetail in the aforementioned copending application.

Referring to FIG. 2, the consumable assembly 16 includes a contact tip24 and the nozzle assembly 22. The nozzle assembly 22 is secured to theconductor tube assembly 40. As shown, the nozzle assembly 22 is securedto a distal end portion 26 of the conductor tube 14. The nozzle assembly22 is substantially cylindrical in one form and receives the distal endportion 26 of the conductor tube 14 therein. In one form, a contact tip24 is coaxially disposed inside the nozzle assembly 22. The nozzleassembly 22 further includes a seating surface 28 that is configured tomate with an end portion 30 of the contact tip 24 (which in one form isspherical as shown, but could be any shape including a linear orpolynomial taper) into the distal end portion 26 of the conductor tube14.

The conductor tube 14 defines an internal passageway 32, and a conduitliner 34 is disposed within the internal passageway 32 as shown. Theconduit liner 34 has a guiding channel 36 for guiding the welding wire(not shown) to the contact tip 24. The conduit liner 34 extends into aninternal cavity 38 of the contact tip 24. The positioning of the conduitliner 34 within the internal cavity 38 provides a continuous guidingchannel 36 for directly feeding the welding wire into the contact tip24. The location of the conduit liner 34 within the internal cavity 38of the contact tip 24 may further reduce the possible jams of thewelding wire by providing a continuous guiding channel 36 and removingany transitions between components that may hang-up of jam the feedingof the welding wire into the contact tip 24. Additional aspects of thelocation and features of the conduit liner 32 within the internal cavity38 of the contact tip 24 has been disclosed in copending U.S.application Ser. No. 13/674,829 titled “Hollow Contact Tip-Diffuser forGMAW Manual/Robotic Arc Welding MIG Guns,” which is commonly owned withthe present application and hereby incorporated by reference in itsentirety.

As shown in FIGS. 4A and 4B, a conductor tube assembly 40 in one form ofthe present disclosure includes a conductor tube 14 having an alignmentdevice 44 for guiding and centrally aligning a conduit liner 32 withinthe conductor tube 14, which will be described in greater detail below.The nozzle assembly 22 is secured to the distal end portion 26 of theconductor tube assembly 40 and pre-tensioned by a collar assembly 50,which will also be described in greater detail below.

Referring back to FIG. 2, the nozzle assembly 22 is secured onto thedistal end 26 of the conductor tube assembly 40, and the contact tip 24engages the seating surface 28 of the nozzle insert 46. As the nozzleassembly 22 is tightened onto a sleeve 60 of the conductor tube assembly40, the seating surface 28 engages against a shoulder of the contact tip24, thereby urging the spherical tapered end 30 of the contact tip 24into a spherical tapered seat 52 of the conductor tube 14. As shown, thecontact tip is wedged between the seating surface 28 and the sphericaltapered seat 52. The wedging between the seating surface 28 and anangled shoulder 54 all function to align the contact tip 24 within theconsumable assembly 16. In addition, as the nozzle assembly 22 istightened onto the conductor tube assembly 40, the collar assembly 50 isbiased against the nozzle body 56, thus providing a pre-tensioning loadagainst the nozzle assembly 22, as discussed below in detail.

As shown in FIGS. 4A-4C, the conductor tube assembly 40 includes asleeve 60 that slides over the profile of the outer surface 49 of theconductor tube 14. The interior profile 80 of the sleeve 60 matches theflat faces 58 of the conductor tube 14 to allow the sleeve 60 to slipfit over the distal end 48. The interior profile 80 and the flat faces58 also provide an anti-rotational feature to prevent the sleeve 60 fromrotating around the conductor tube 14. It should further be appreciatedthat the anti-rotation feature could include various cross-sectionalshapes that offer flat, angled, or other non-matching profiles toinhibit the rotation of a mating component that slips over the distalend 48, and thus the forms illustrated and described herein should notbe construed as limiting the scope of the present disclosure.Additionally, the sleeve 60 may include various geometries on aninterior profile 80 for mating and sliding over the distal end 48 of theconductor tube 42. For example, the sleeve 60 may include configurationsthat allow for a greater contact area with the outer surface of theconductor tube 14 for improving the conduction heat transfer from theconsumable assembly 16 to the conductor tube 14, such as, by way ofexample, a hexagonal configuration.

Referring to FIG. 4C, the sleeve 60 is secured to the conductor tube 14in one form by the set screw 64 that is engaged through a threadedaperture 92 of the sleeve 60. The threaded aperture 92 is aligned withthe threaded opening 62 of the conductor tube 14, and the set screw 64removably secures the sleeve 60 in position over the distal end 48 ofthe conductor tube 14.

In one form, the sleeve 60 (FIG. 5) is threaded and includes threads 76on its exterior surface as shown. The thread geometry and design canvary according to the desired torque and retention characteristics. Inone form, the threads 76 may be of a standard pitch, and in anotherform, the thread pitch may be variable to improve retention of theconsumable assembly 16. For example, the sleeve 60 in one form includesa leading taper of threads 78 that create a guide to initially align theconsumable assembly 16. In one form, the leading taper 78 is created byvarying a height of each thread 76 from the proximal end portion to thedistal end portion of the sleeve. A maximum thread height is toward theproximal end portion 84 of the sleeve 60 and a minimum thread height isadjacent the distal end portion 86 of the sleeve 60. The leading taper78 provides for easier alignment with the mating components, and thisparticular thread design also reduces the possibility of cross threadingmating components. In another form, the sleeve 60 may optionally includea rounded front surface 95 for further assisting with the alignment ofthe mating components.

The sleeve 60 may be manufactured by various methods including machiningor a metal injection molding process, also known as MIM. The sleeve 60manufactured by a MIM process allows for more complex geometries thatare difficult to machine, by molding in more intricate shapes andfeatures of the body 83 and the interior profile 80, for example, thetab 82 feature as previously set forth. These additional features mayallow for additional protection of the conductor tube assembly 40 and/ormay also include improvements to the heat transfer from the consumableassembly 16 by increasing the contact area between the sleeve 60 and theconductor tube 14, such as, by way of example, a hexagonalconfiguration, among others

The sleeve 60 may be made of various hardened metals and alloys, such asa stainless steel alloy that resists deformation and impact damage. Thesleeve 60 also provides additional strength to the distal end 48 of theconductor tube 14, since the copper material of the conductor tube 14 isrelatively malleable. The conductor tube assembly 40 further addressesthe issue of damaging threads on a conventional conductor tube assemblysince the sleeve 60 is removable and replaceable.

Referring to FIGS. 6A-6D, in one form, the conductor tube assembly 40includes a collar assembly 50. In one form, the collar assembly 50comprises a collar body 98, a wave spring 100 and a locking ring 102.The collar body 98 defines an exterior surface 106 and an interior bore108. The collar body 98 includes an internal flange 104 disposed at adistal end portion 110 of the collar body. The internal flange 104projects radially and inwardly and defines an opening 114 have a distaldiameter that is large enough to allow the collar assembly 50 to slideonto the distal end 26 of the conductor tube 14.

As shown in FIG. 6D, the collar body 98 has a distal end portion 110 anda proximal end 99. The distal diameter 113 of the opening 114 in thedistal end 97 is smaller than the proximal diameter 115 of the interiorbore 108 at the proximal end 99. The wave spring 100 is positionedwithin the interior bore 108 of the collar body 98. When the collarassembly 40 is assembled onto the conductor tube 14, the wave spring 100is disposed within an area or gap between the conductor tube 14 and thecollar body 98 as shown. In another form, the collar body may define theexterior surface 106 and the interior bore 108 and the area for the wavespring is between formed by the changing diameters of the interior bore108. In this form, the wave spring may bias the collar body against thedistal end portion 110 having a distal diameter 113 smaller than theproximal diameter 115.

The conductor tube 14 in one form defines a circular grove 116, in whichthe locking ring 102 is disposed. The locking ring 102 engages withinthe circular groove 116 to hold the wave spring 100 in position andprovides a surface for the wave spring 100 to create the biasing forceagainst the internal flange 104. The wave spring is only one example ofthe various springs and the spring may provide a constant bias rate orbe variable to provide the necessary force for the application.

In another form, the conductor tube may be integrally formed with anoutward protrusion and eliminating the locking washer discussed above.The outward protrusion would engage the proximal side of the wave springin the same manner at the locking washer, discussed above. The outwardprotrusion in still another form is a shoulder that may be machined intothe distal end of the conductor tube.

Referring to FIG. 7, the collar body 98 is secured in position on theconductor tube 14 by the sleeve 60. The collar body 98 is moveable,along a longitudinal axis A, between the proximal end portion 84 of thesleeve 60 and the locking ring 102, as indicated by directional arrow113. The wave spring 100 creates a biasing force against the internalflange 104 and resists movement of the collar body 98 away from thedistal end 48 of the conductor tube. The biasing force is used toprovide pre-tensioning force against the consumable assembly 16 securedon the threads 76.

As shown in FIG. 8, the consumable assembly 16 is secured against thecollar body 98 causing the collar body 98 to move away from the distalend portion 84 of the sleeve 60. The wave spring 100 resists themovement of the collar body 98 with the biasing force, in the directionof arrow 112, which pre-tensions the engagement of the consumableassembly 16 on the threads 76 of the sleeve 60. The pre-tensioningengagement with the collar assembly 50 provides resistance against theconsumable assembly 16 inadvertently loosening during operation of thewelding gun. The exterior surface 106 of the collar body 98 may furtherinclude angled surfaces or other gripping features, such as knurls orscallops, to allow for ease of use when securing and removing theconsumable assembly 16 from the conductor tube assembly 40.

FIG. 9 summarizes and illustrates components of the conductor tubeassembly 40 and the consumable assembly 16. The consumable assembly 16includes the nozzle assembly 22 and the contact tip 24. The consumableassembly 16 is secured to the distal end 48 of the conductor tube 14 viathe sleeve 60, and the collar assembly 50 pretensions the consumableassembly 16 to the conductor tube assembly 40, as previously set forth.

Referring to FIGS. 10 and 11A to 11D, a collar assembly 50 includes acollar body 98. The collar body 98 includes indicia 208 for allowing anozzle distance 209 to be set by aligning a proximal opening 150 of thenozzle body 174 with the desired nozzle distance 209. In one form thereis an initial position and three additional positions for setting thenozzle distance 209. As shown in FIG. 11A, an initial exemplary positionwhere a distal end face 124 of the contact tip 46 is recessed within thenozzle body 174 to the nozzle distance 209 of approximately ¼ inches.Referring to FIG. 11B, an example of a first position is shown with thedistal end face 124 of the contact tip is recessed within the nozzlebody 174 to the nozzle distance 209 of approximately ⅛ inches. As shownin FIG. 11C, an example of a second position is shown and in this form,the distal end face 124 of the contact tip 46 is flush with the distalopening 152 of the nozzle body 174. Referring to FIG. 11D, anotherexample of a third position is shown with the distal end face 124 of thecontact tip 46 protruding beyond the distal opening a nozzle distance ofapproximately ⅛ inches. Therefore, the indicia 208 on the collar body 98is used to allow the user to quickly adjust the nozzle position withouthaving to perform any manual measurements between the distal opening 152of the nozzle body 174 and the distal end face 124 of the contact tip46. It should be understood that the specific dimensions of ¼ and ⅛inches are merely exemplary and should not be construed as limiting thescope of the present disclosure.

The previous examples are not suggested to limit other variations andare presented to teach possible embodiments of this disclosure.

The present disclosure is merely exemplary in nature and, thus,variations that do not depart from the spirit of the disclosure areintended to be within the scope of the present disclosure. Suchvariations are not to be regarded as a departure from the scopecontemplated in the present disclosure.

What is claimed is:
 1. A collar assembly for use in securing a nozzleassembly to a welding torch, the welding torch including a conductortube that includes a recess in an external surface of the conductortube, the collar assembly comprising: a collar body defining an exteriorsurface and an internal bore; an internal flange extending radiallyinwardly and disposed at a distal end portion of the collar body; a wavespring, the wave spring having a first end disposed against the internalflange; and a locking ring disposed against a second end of the wavespring, wherein the locking ring is positioned within the recess of theexternal surface of the conductor tube.
 2. The collar assembly accordingto claim 1, wherein the exterior surface of the collar body is profiled.3. The collar assembly according to claim 2, wherein the profiledexterior surface is flared.
 4. The collar assembly according to claim 2,wherein the profiled exterior surface defines a plurality of grippingridges.
 5. The collar assembly according to claim 1, wherein theexterior surface of the collar body includes indicia on the exteriorsurface for allowing a nozzle distance to be set.
 6. The collar assemblyaccording to claim 1, wherein the collar body further defines a distalend portion that extends radially and inwardly defining a distaldiameter and a proximal portion wherein the diameter of the internalbore is larger than the distal diameter.
 7. A collar assembly for use insecuring a nozzle assembly to a welding torch, the welding torchincluding a conductor tube that defines a circular groove in an externalsurface of the conductor tube, the collar assembly comprising: a collarbody defining an exterior surface and an internal bore; an internalflange extending radially inwardly and disposed at a distal end portionof the collar body; a wave spring having a first end disposed againstthe internal flange; and a locking ring disposed against a second end ofthe wave spring and received in the circular groove of the conductortube.
 8. The collar assembly according to claim 7, wherein the exteriorsurface of the collar body is profiled.
 9. The collar assembly accordingto claim 8, wherein the profiled exterior surface is flared.
 10. Thecollar assembly according to claim 8, wherein the profiled exteriorsurface defines a plurality of gripping ridges.
 11. The collar assemblyaccording to claim 7, wherein the exterior surface of the collar bodyincludes indicia on the exterior surface for allowing a nozzle distanceto be set.
 12. The collar assembly according to claim 7, wherein thecollar body further defines a distal end portion that extends radiallyand inwardly defining a distal diameter and a proximal portion whereinthe diameter of the internal bore is larger than the distal diameter.13. A conductor tube assembly of a welding torch configured to bereceived by a nozzle assembly, the conductor tube assembly comprising: aconductor tube having a proximal end, a distal end configured to bereceived within the nozzle assembly, an external surface, and a lockingring integrally formed on the external surface proximate to the distalend; and a collar assembly disposed around the external surface of theconductor tube proximate to the distal end, the collar assemblycomprising: a collar body defining an exterior surface and an internalbore; an internal flange extending radially inwardly and disposed at adistal end portion of the collar body; and a wave spring, the wavespring having a first end disposed against the internal flange and asecond end disposed against the locking ring of the conductor tube. 14.The conductor tube assembly according to claim 13, wherein the exteriorsurface of the collar body is profiled.
 15. The conductor tube assemblyaccording to claim 14, wherein the profiled exterior surface is flared.16. The conductor tube assembly according to claim 14, wherein theprofiled exterior surface defines a plurality of gripping ridges. 17.The conductor tube assembly according to claim 13, wherein the exteriorsurface of the collar body includes indicia for allowing a nozzledistance to be set.
 18. The conductor tube assembly according to claim13, wherein the collar body further defines a distal end portion thatextends radially and inwardly defining a distal diameter and a proximalportion wherein the diameter of the internal bore is larger than thedistal diameter.
 19. The conductor tube assembly according to claim 13,wherein the wave spring imparts a biasing force against the internalbore to bias the collar body toward the distal end of the conductortube.
 20. The conductor tube assembly according to claim 19, wherein thebiasing force biases the collar body against the nozzle assembly whenthe distal end of the conductor tube is received within the nozzleassembly in order to provide a pre-tensioning force against the nozzleassembly.